Users of X-ray film processors have had a choice between two different types of machines. The first type, a small machine, processes a relatively small number of films but operates on the usual house current of 120 volts. As the alternative, a heavy-duty machine can develop a significantly greater number of films; however, it requires a power supply of 240 volts to meet the machine's requirements for electrical current.
The light-duty processor, the first type mentioned above, generally has small tanks of developer, fixer, and washing solutions as well as a small drying area. As a consequence, it requires relatively little electric current to sufficiently heat these areas to the appropriate temperatures for developing and drying X-ray film. Thus, they generally operate on the usual house electrical supply of 120 volts and use amounts of current considered permissable for such circuits.
The relatively small volume in the various sections of the processor, however, limit the number of films that can pass through it during any particular time period. Moreover, the film must move slowly through the processor in order to remain in each section for an acceptable period of time. Thus, this type of machine, in an hour, can generally process, at most, no more than about 100 pieces of 14 inch by 17 inch X-ray film.
Thus, over a set time period, the smaller machines discussed above have a limited capacity. The large, or heavy-duty, processors overcome this drawback. The number of 14 inch by 17 inch pieces of film these machines can handle may even exceed 175 pieces per hour. These greater capacity processors, however, require large-volume tanks of developer, fixer, and washing solutions as well as a large drying area. These must remain at sufficiently warm temperatures to assure the proper processing of the film in the alloted times during which it travels through the various areas of the machine. To keep the sections of the processor sufficiently warm, the machine includes separate heaters for its developer solution, fixer solution, and drying area. Powering these heaters, as well as operating the remaining components of the processor, generally requires an amount of power that precludes the use of a 120-volt supply of electrical current; the processor would require substantially more than the 20 amps. of current generally permitted for outlets providing 120-volt electricity.
Consequently, heavy-duty processors require 240 volts. As a result, the user must install special electrical service for this piece of equipment. This, in turn, may involve a substantial investment to rewire the dark room and, perhaps, even the central distribution box for the facility.
As a consequence, the user generally has to decide between a light-duty or a heavy-duty processor. The former may not have sufficient capacity for his needs, while the latter may entail a large expenditure to provide it with the required electrical service.